作业帮since后跟一个时间点,动词用过去式.for后跟一段时间.动词用完成时
来源：学生作业帮 编辑：作业帮 分类：英语作业 时间：2024/05/04 05:38:11
since后跟一个时间点,动词用过去式.for后跟一段时间.动词用完成时
究竟想问什么?这个是对还是错?
再问： since,for的用法区别，详细点
再答： since 副词 ad. (常用于现在完成时或过去完成时) 1. 此后;从那时到现在 She left school three years ago and has worked as a nurse ever since. 她三年前毕业,从那时起便一直当护士。 2. 之前,以前 介词 prep. 1. (常用于现在完成时或过去完成时)自...以来,从...至今 I haven't heard from him since last year. 我自去年以来未曾收到过他的信。 连接词 conj. 1. (常用于现在完成时或过去完成时)自...以来,从...至今 It's been ten years since they married. 他们结婚到现在已经十年了。 She has been living a hard life since her husband died. 她自从丈夫死后,一直过着艰苦的生活。 2. 既然;因为,由于 He must have taken the book since it isn't here. 他一定是把书拿走了,因为书已不在这里了。 Since it is so hot, let's go swimming. 既然天气这么热,我们去游泳吧。 For for 介词 prep. 1. 为,为了 They fought for national independence. 他们为民族独立而战。 This letter is for you. 这是你的信。 2. 代替;代表 We used boxes for chairs. 我们用箱子当椅子坐。 3. 因为,由于 I am sorry for what I said to you. 我后悔不该对你讲那些话。 4. 在(指定时间) The meeting is arranged for 9 o'clock. 会议安排在九点钟。 5. (表示时间、距离等)达,计 You can see for miles from the roof. 你站在屋顶上可以看到数英里之外。 6. 对于,关于;在...方面 I am too old for the job. 我年纪太大,做不了这工作。 7. 为得到,为赢得 He sent the waiter for a packet of cigarettes. 他让侍者去拿一盒香烟。 8. 以...为代价;以...交换 He sold his car for 500 dollars. 他以五百元把车卖了。 9. 当作,作为 Do you take me for a millionaire? 你是不是把我当百万富翁? 10. 赞成;支持;倾向于 Are you for the government or against it? 你是支持还是反对政府? 11. 朝...方向去;往,向 He left for Taipei. 他出发去台北。 12. 就...而言 She is sophisticated for her age. 就年龄而言她是世故了一点。 连接词 conj. 1. 因为,由于 We must start early, for it will take two hours to drive to the airport. 我们得早点动身,因为开车去机场得花两个小时
再问： since,for的用法区别，详细点
再答： since 副词 ad. (常用于现在完成时或过去完成时) 1. 此后;从那时到现在 She left school three years ago and has worked as a nurse ever since. 她三年前毕业,从那时起便一直当护士。 2. 之前,以前 介词 prep. 1. (常用于现在完成时或过去完成时)自...以来,从...至今 I haven't heard from him since last year. 我自去年以来未曾收到过他的信。 连接词 conj. 1. (常用于现在完成时或过去完成时)自...以来,从...至今 It's been ten years since they married. 他们结婚到现在已经十年了。 She has been living a hard life since her husband died. 她自从丈夫死后,一直过着艰苦的生活。 2. 既然;因为,由于 He must have taken the book since it isn't here. 他一定是把书拿走了,因为书已不在这里了。 Since it is so hot, let's go swimming. 既然天气这么热,我们去游泳吧。 For for 介词 prep. 1. 为,为了 They fought for national independence. 他们为民族独立而战。 This letter is for you. 这是你的信。 2. 代替;代表 We used boxes for chairs. 我们用箱子当椅子坐。 3. 因为,由于 I am sorry for what I said to you. 我后悔不该对你讲那些话。 4. 在(指定时间) The meeting is arranged for 9 o'clock. 会议安排在九点钟。 5. (表示时间、距离等)达,计 You can see for miles from the roof. 你站在屋顶上可以看到数英里之外。 6. 对于,关于;在...方面 I am too old for the job. 我年纪太大,做不了这工作。 7. 为得到,为赢得 He sent the waiter for a packet of cigarettes. 他让侍者去拿一盒香烟。 8. 以...为代价;以...交换 He sold his car for 500 dollars. 他以五百元把车卖了。 9. 当作,作为 Do you take me for a millionaire? 你是不是把我当百万富翁? 10. 赞成;支持;倾向于 Are you for the government or against it? 你是支持还是反对政府? 11. 朝...方向去;往,向 He left for Taipei. 他出发去台北。 12. 就...而言 She is sophisticated for her age. 就年龄而言她是世故了一点。 连接词 conj. 1. 因为,由于 We must start early, for it will take two hours to drive to the airport. 我们得早点动身,因为开车去机场得花两个小时